Length vs Length() Method in Java

Computing the length of a value or a container is essential in all programming languages. This functionality is assistive for the developer in analyzing the applied code features and updating and enhancing the code based on that. To achieve this, Java provides “length” and “length()” in Java that can be applied to evaluate the length in distinct cases.

This guide will discuss the differences between Java “length” and “length()”.

What is “length” in Java?

The “length” corresponds to a property that can be applied to an array to compute its length but cannot be applied to strings.

Example 1: Applying the “length” Property

This example demonstrates the concept of the “length” property:

public class Lengthdiff {
 public static void main(String[] args) {
  int[] array= new int[5];
  System.out.println("Array Length -> "+ array.length);
}}

In the above code lines, create an integer array allocated the size of “5”. After that, apply the “length” property upon the array to retrieve the array’s length.

Output

In this output, it can be seen that the allocated array’s length is displayed accordingly.

Note: The length of the array comprising elements in it can also be computed which will be discussed later in this blog.

Example 2: Limitations With the “Length” Property

The discussed property is not suitable for the string values as in such a scenario, it returns an exception instead, as follows:

public class Lengthdiff {
 public static void main(String[] args) {
  String x = "John";
  System.out.println("Array Length -> "+ x.length);
}}

According to this block of code, define a string value and return its length via the applied “length” property.

Output

This output verifies that the “length” property is not applicable to the string values.

What is the “length()” Method in Java?

The “length()” is a final method that can be applied to the strings and retrieves the number of characters contained in the string but cannot be applied to an entire array.

Example 1: Applying the “length()” Method

This demonstration utilizes the “length()” method to return the defined string’s length:

public class Lengthdiff {
 public static void main(String[] args) {
  String givenString= "Java Programming";
  System.out.println("String Length -> "+ givenString.length());
}}

In these code lines, initialize the stated string. Next, apply the “length()” method to return the string’s length.

Output

Example 4: Limitations With the “length()” Method

This particular method cannot be applied to an array. It is such that it returns an exception instead upon doing so:

public class Lengthdiff {
 public static void main(String[] args) {
  String[] givenString= {"Java", "Programming"};
  System.out.println("String Length -> "+ givenString.length());
}}

In this code, define an array of “String” type and return its length via the “length()” method.

Output

Here, it can be visualized that an exception is retrieved instead upon invoking the discussed method upon an array.

However, this method can be used to return a target value’s length in an array via indexing as follows:

As observed, the length of the array element i.e., “Java” is returned accordingly.

Core Differences Between “length” and “length()” in Java

Conclusion

In Java, the “length” property is applied to compute the array’s length and cannot be applied to strings whereas the “length()” method gives the length of the string and retrieves the number of characters contained in the string.